Sewing machine



Sept. 27, 3949.

N. V. CHRESTENSEN ETAL.

SEWING MACHINE 3 Sheets-Sheet 1 Filed April 18, 1946 INVENTOR BY fi.

ATTOME p 1949- N. v. CHRISTENSEN ET AL 2,483

SEWING MACHINE Filed April 18, 1948 3 Sheets-Sheet 2 mug lllElll.nwullulllii 7 lllllllllr 56 INVENTORS ATTORNEY Sept. 27, 1949. N. v.CHRlSTENSEN ET AL SEWING MACHINE 3 Sheets-Sheet 3 Filed April 18, 1946 IINVENTOR. BMW

Patented Sept. 27, 1949 UNITED STATES SEWING MACHINE IllinoisApplication April 18, 1946, Serial No. 663,122

6 Claims. (01. 112218) This invention relates to devices adapted to beassociated with sewing machines for delivering a stream of cooling airto the zone or region of movement of the needles so as to preventoverheating of the needles even when the machines are operated at highspeed upon relatively coarse and heavy fabrics The devices also areadapted to remove lint and other small particles from the region inwhich stitching takes place.

An object of the invention has been to provide a simple, compact, andeffective arrangement for creatin and delivering a stream of air forneedle cooling and lint removing purposes.

Another object has been to provide needle cooling and lint removingmeans, in association with a sewing machine, which is inexpensive bothto construct and to operate.

A further object of the invention has been to so provide and arrangedevices of the character indicated as to enable the ready adjustment ofthe air delivery means to bring about the most effective delivery of thestream of air for the particular purposes of a specific machine or aspecific operation.

One feature of the invention is the provision of a connection from theregular operating means for the sewing machine for driving a blowerwhich constitutes the source of the stream of air. This connection issuch that the speed at which the blower is driven is dependent upon thespeed of operation of the machine. Accordingly, if the speed of themachine is increased, the speed of the blower is also increased and. areater amount of cooling air will be delivered to the zone of movementof the needle or needles. This is advantageous since the need for thecooling action increases with the speed of operation of the machine.

Preferably the blower, or the source of air supply, is driven at ahigher speed than the speed of operation of the machine. Normally thetwo speeds may be at a ratio of about 2 to 1. However, for some purposesthe speed of rotation of the blower rotor may be 3 or 4 times that ofthe drive shaft of the sewing machine. This enables the benefits of theinvention to be derived in connection with operations at relatively slowspeed upon exceptionally heavy and coarse materials.

Another feature of the invention is the provision of a simple, readilyadjustable support and drive for a blower which carries ample lubricantfor a long period of operation.

A special feature or advantage of the invention is that the adjustablemounting of the blower, or other air current source, on the supportingtable is such that it provides a simple and efiective means for varyingthe tension of the belt which connects the sewing machine with the powersource.

Other objects, features, and advantages of the invention will appearfrom the detailed description of certain illustrative embodiments of thesame, which will now be given in conjunction with the accompanyingdrawings, in which:

Figure l is an elevational view of a fragmentary portion of a supportongtable carrying a sewing machine, the power means for driving the same,and a blower and associated devices forming part of the presentinvention,

Figure 2 is an enlarged detail view showing, in longitudinal section, aportion of the conduit embodied in Figure 1;

Figure 3 is an enlarged end view of the arrangement shown in Figure 1,as seen from the left in said figure;

Figure 4 is a detail View in horizontal section along the line 44 ofFigure 3;

Figure 5 is a side elevational view, with a portion broken away forclarity of illustration, showing a modified support for the blower; and

Figure 6 is a plan view of the support and blower shown in Figure 5 witha top cover plate removed from the support and with a pulley applied tothe driven shaft of the unit.

Turning now to the drawings and referring particularly to Figures 1 to4. there is shown a supporting table Ill, which, it will be understood,is carried by any suitable leg structure. The table is preferably of areadily portable or shiftable type, enabling movement of the unit intoany desired position in a line. On the upper surface of the table Hithere is suitably secured, a sewing machine H which may be of anydesired construction. The machine illustrated is of the type disclosedin Patent No. 1.741.095, granted to Norman V. Christensen and Harold J.Le Vesconte, on December 24, 1929. Beneath the table In there is mounteda power unit IQ of any suitable construction, preferably of the typedisclosed in the pending application of George Sauer and Clarence C.Smith, Serial No. 638,186. filed on December 29, 1945. commonly known asan electric transmitter, in-- cludes an electric motor 13 and a clutch Mhavin an axially shiftable, driven shaft 15 which carries a pulley it.For further details as to the construction and operation of the powerunit reference may be had to said Sauer and Smith application. Theclutch is adapted to be This power unit engaged by the operation of alever or arm I! through connections from a foot treadle or the like.Rocking of the arm in a counter-clockwise direction, in opposition to aspring i8, serves to shift the shaft l5 and the associated driven clutchmember axially toward the left and causes the pulley 16 to be driven atthe speed of the motor, which is usually 3450 R. P. M. A belt !9 servesto connect the pulley It with the combined pulley and handwheel 20 ofthe sewing machine for driving the latter. It will be understood that solong as the clutch is engaged and the sewing machine is driven, thestitch forming instrumentalities of the latter, including one or moreneedles 25, will be operated and the work introduced between a presserfoot 22 and a work supporting arm 23- will be fed in proper relation tothe stitch forming means.

The means for producing the desired current of cooling and lint removingair across the zone of operation of the needles comprises a blower 24which may be of any suitable construction, but is preferably of arelatively small type capable of high speed operation and of generatinga current of air in sufficient volume and under suflicient head toproduce the desired needle cooling effect. A small blower, such as thetype sold under the trade name Airotor, which requires only a smallfraction of a horsepower, less than say horsepower for its operation,has been found quite satisfactory for the purpose. The blower is mountedon a Z-shaped bracket 25 which is adjustably secured to the top of thetable II! by means of screws 25. These screws cooperate with elongatedslots 21 in the lower, horizontally disposed leg 23 of the bracket. Theblower has a housing 29 which is secured to the underside of the upperhorizontal leg 30 of the bracket by means of a plurality of screws 3 lThe blower housing has a laterally extending flange provided around itsdischarge outlet and this flange receives the screws 3|. The blower hasa rotor 32, preferably of squirrel cage construction, mounted on andsecured to a shaft 33 which is carried by a bearing lug 34 secured bywelding or the like to the vertically disposed leg 35 of the Z-bracket.It will be understood that the shaft 33 extends into the housing 29 andcarries the rotor within the latter. At its opposite end the shaft 33carries a pulley 36 which is secured for rotation with the shaft andwhich is adapted to bear against a portion of the belt 19 as shown inFigures 1 and 3. If the belt is of V-shape in crosssection, the pulley36 preferably bears against the fiat outer surface of the belt and forthis purpose is provided with a cylindrical outer face, while the sewingmachine and transmitter pulleys preferably have V grooves. The housing29 is provided with relatively large openings in both of its side walls,these openings being in axial alinement with the rotor. The opening onthe side toward the vertical portion 35 of the Z-bracket may suitably besomewhat smaller than the diameter of the rotor, while the opening onthe opposite side of the housing, as shown in Figure 3, is preferablyslightly larger than the outer diameter of the rotor, so that the lattermay be inserted through this opening and mounted on or removed from theshaft without removal of the housing. A small ring member 3! may beprovided on the outer face of the housing to cover a sufiicient portionof the opening in this face to reduce the diameter of the remainingopening to slightly less than that of the rotor. For the purpose oflubricating the bearings for the shaft 33 there is preferably provided aGits oil cup 38 which is adapted to supply oil to the central portion ofthe bearing lug 34. A small annular space may be provided around theshaft at this point by the provision of bearing bushings at each end ofthe bearing lug 34. This space assists in delivering the oil to thesurfaces requiring lubrication.

The laterally extending portion of the upper leg 30 of the Z-bracket isprovided with a screw threaded opening which is in line with the outletfor the blower housing 29. This opening is adapted to receive a splitcoupling fitting 39 which, in turn, receives the lower end of a metaltube 40. As the fitting 39 is screwed into the threaded aperture it willbe squeezed more tightly around the tube 40 and will clamp the same inany desired position. This enables both vertical and angular adjustmentof the tube. If desired the tube may be of one continuous lengthextending from the blower to a point adjacent the zone of operation ofthe needles. However, in order to provide further and more accurateadjustment of the discharge end of the tube, it is preferably formed intwo sections. The outer section il is secured to the section 40 by meansof a coupling 42, Figure 3, which, as best shown in Figure 2, comprisesa sleeve member 43 having threaded portions at both ends adapted toreceive nut elements as and Q5. The element 34 serves to clamp anenlarged portion 46 adjacent the end of the tube 50 to the end of thefitting 53. Element 45 serves to clamp packing material 41 against theopposite end of the element 43 and against the outer surface of the tubea l. As shown in Figure 3, the axis of the coupling (32 is preferablyhorizontal so as to allow swinging of the tube 4| about a horizontalaxis at its upper end. If desired thearrangement may be such that thisswinging movement may be imparted without loosening of the nut element55, the friction being such as to cause the tube to remain in any setposition. This would be desirable if it were found necessary in theoperation of the machine to discontinue the blowing of air across thezone of operation of the needles.

It will be seen that by virtue of the plurality of adjustments madepossible by the positioning of the bracket 25' on the table, by theclamping of the tube 40 within the member 39, and by the coupling of thetubes 40 and 4|, the position of the discharge end of the tube 4| may bevaried, if desired, to suit the particular requirements of aninstallation or a particular operation of the machine. Tubes 40 and Mare preferably about of an inch in diameter so that an adequate amountof air may be delivered, for needle cooling purposes, at a velocitycapable of being developed by a small blower of the type indicated,driven at high speed, i. e., between say 6000 and 12,000 R. P. M. Inthis connection it should be observed that the size of the pulley 36 issuch, in relation to the pulleys I6 and 20, that the blower rotor willbe rotated at a much higher angular speed than the main shaft of thesewing machine, The arrangement may be such, for example, that theblower rotor will be driven at double the speed of the machine and thus,if the latter is driven at 4000 R. P. M. the rotor or impeller of theblower will rotate at 8000 R. P. M. Under these conditions a relativelysmall blower, having a rotor of say 2 inch diameter, is capable ofsupplying cooling air to the zone of operation of the needles at avelocity and in such quantity as to effect substantial cooling of theneedles. The results obtained may be comparable with those set forth inthe Rubel application, Serial No. 433,740 new Patent No. 2,423,996,dated July 15, 1947.

As explained in said Rubel application, it is desirable that the coolingair be delivered at a velocity of between and 100 ft./sec.,-prefer ablybetween 50 and 80 ft./sec., in an amount equal to between .1 and .3 cu.ft. per sec. To accomplish this, the blower is preferably capable ofdeveloping a head of between 1.0 and 2.5 inches of water. In general,the principles and conditions set forth in said Rubel application may beconsidered applicable.

Referring now to Figures 5 and 6, there is shown a modified arrangementof the blower and supporting means therefor. A supporting bracket 48 isprovided. This has a main central portion 49 of inverted U-shapedconstruction and has end angle members 50 and 5| secured to the part 49in any suitable way, as by welding. Each of the angle members isprovided with an outturned foot 52 at its lower end having one or moreelongated slots 53 therein for adjustable securement of the support tothe top of the table by means of screws. A shaft 54 is mounted withinbushings 55 in the opposite legs of the U- shaped member 49. On theouter projecting end of the shaft 54 there is secured a pulley 56 which,as in the first embodiment, is adapted to cooperate with the drivingbelt IQ of the sewing machine. Within the chamber formed between thelegs of the U-shaped member 49 and the end angle members 50 and 5|,there is secured to the shaft 54 a gear 51. The latter meshes with apinion 58 secured to a shaft 59 mounted in bushings 60 carried by thelegs of the member 49.

Shaft 59 projects outwardly from the member if) at the opposite sidefrom that at which the pulley 56 is mounted and it carries the rotor iiiof a blower 62 which may be of substantially the same construction asthe blower disclosed in connection with Figure 1. The housing 53 of thisblower, however, in lieu of having its discharge outlet disposed withits axis vertically, is arranged at an angle, as best shown in Figure 5.Flange 6d at the discharge end of the housing is secured by screws 65 toa plate-like, lateral extension 65 of the angle member 50. Thisplate-like extension projects laterally from the vertical leg of theangle member 50 and at its upper end is inclined at an appropriateangle, say to the vertical. A split clamping element Bl, havingscrewthreaded engagement with the plate 66, serves to grip and retainthe tube 68. This tube may be of generally the same construction as thetube 40, M of the first embodiment or it may be of a single continuoustube of appropriate shape. A cover plate 69 is provided at the top ofthe support to retain lubricant within the pocket formed between thelegs of the member 59 and the angle members and 5!. It may be retainedin any suitable way, as by means of screws. A Gits cup 10 secured to thecover 6!! permits the introduction of lubricant whenever required.

Gear 51 and pinion 58 may be so related as to provide any desired ratiobetween the speeds of the pulley 56 and the rotor 6 I. In theillustrated embodiment the ratio is 2 to 1. Assuming, for example, thatthe pulley is rotated at 4000 R. P. M., the rotor 5! will be rotated at8,000 R. P. M. As in the first embodiment, the pulley 56 may be rotatedat a higher speed than the main drive shaft of the sewing machine. Thisarrangement insures the delivery of an adequate stream of cooling air toeffect cooling of the 6. needles even though the sewing machine mayitself be operated at a relatively slow speed.

While several illustrative embodiments of the invention havebeen-disclosed in considerable detail, it will be understood thatnumerous changes may be made in the construction and arrangement of thevarious parts without departing from the general principles and scope ofthe invention.

A The specific dimensions, speeds, and the like given in the foregoing,are to be understood to be simply illustrative of suitable embodimentsof the invention.

What we claim is:

1. In combination a supporting member, a sewing machine carried by saidmember, said machine having stitch-forming devices including a needle,means including a belt for delivering power to said sewing machine fordriving the same, a bracket adjustably mounted on said supporting memberat a point adjacent said belt, a small low-pressure blower carried bysaid bracket, means for driving said blower including a shaft supportedby said bracket and having a pulley secured thereto in a position forfrictional engagement with said belt, said pulley being shiftabletowardand away from said belt in the plane of the pulley upon adjustmentof said bracket and conduit adjustably mounted on said bracket, andwholly supported thereby said conduit being connected with the outlet ofsaid blower and being arranged to deliver a stream of cooling airtherefrom to the zone of operation of said needle.

2. In combination a supporting member, a sewing machine carried by saidmember, said machine having stitch-forming devices including a needle,means including a belt for delivering power to said sewing machine fordriving the same, a bracket adjustably mounted on said supporting memberat a point adjacent said belt, a blower carried by said bracket, meansfor driving said blower including a shaft supported by said bracket andhaving a pulley secured thereto in position for frictional engagementwith said belt, said pulley being shiftable toward and away from saidbelt in the plane of the pulley upon adjustment of said bracket and aconduit mounted for axial and angular adjustment on said bracket, andwholly supported thereby said conduit being connected with the outlet ofsaid blower and being arranged to deliver a stream of cooling airtherefrom to the zone of operation of said needle.

3. In combination a supporting member, a sewing machine carried by saidmember, said machine having stitch-forming devices including a needle,means including a belt for delivering power to said sewing machine fordriving the same, a bracket adjustably mounted on said supporting memberat a point adjacent said belt, a small low-pressure blower carried bysaid bracket, means for driving said blower including a shaft supportedby said bracket and having a pulley secured thereto in position forfrictional engagement with said belt, said pulley being shiftable towardand away from said belt in the plane of the pulley upon adjustment ofsaid bracket and a conduit adjustably mounted on said bracket for axialadjustment thereon and for bodily movement therewith, said conduit beingconnected with the outlet of said blower and being arranged to deliver astream of cooling air therefrom to the zone of operation of said needle,said conduit comprising a plurality of swivelly connected sectionsarranged to be frictionally held in any selected relation to each other,thereby enabling angular adjustment of the discharge end thereof into adesired active position or into an inactive position.

4. In combination a supporting structure comprising a table top, asewing machine having a main drive shaft with apower receiving pulleythereon, said machine having stitch-forming devices including a needle,power supplying means including a belt cooperating with said pulley, asupport member, means for adjustably securing said support member tosaid table top adjacent 10 said belt, a shaft carried by said supportmember and having a pulley secured thereto for cooperation with saidbelt, the adjustment of said support member being adapted to shift saidpulley in the plane of said belt to vary the tension thereof, a small,high speed blower mounted on said member, said blower having a rotorarranged to be driven by said shaft, the connection between said shaftand said rotor being such as to drive said rotor at a higher angularspeed than that of 20 said shaft, and a conduit connected with saidsupport member and arranged to deliver a stream of cooling air from saidblower to the zone of operation of said needle.

5. In combination a supporting member, a sewing machine carried by saidmember, said machine having stitch-forming devices including a needle,means including a belt for delivering power to said sewing machine fordriving the same, a bracket adjustably mounted on said sup- 30engagement with said belt, and a conduit connected with the outlet forsaid blower and arranged to deliver a cooling stream of air to the zoneof operation of said needle of said sewing machine.

6. In combination a supporting member, a sewing machine carried by saidmember, said machine having stitch-forming devices including a needle,means including a belt for delivering power to said sewing machine fordriving the same, a bracket adjustably mounted on said supporting memberat a point adjacent said belt, said bracket being of generally Z-shapedconfiguration, means for securing one leg of said Z-shaped bracket tosaid supporting member, a blower carried by the opposite leg of saidZ-shaped bracket, means for driving said blower including a shaftsupported by the intermediate connecting portion of said bracket, andhaving a pulley secured thereto in position for frictional engagementwith said belt, said opposite leg of the bracket having a threadedopening in line with the outlet of said blower, and a conduit having oneend adjustably connected with said bracket at said threaded opening andits other end positioned adjacent the zone of operation of said needle,said conduit being wholly supported by said bracket.

NORMAN V. CHRISTENSEN. CLARENCE 0. SMITH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 286,146 Neely Oct. 2, 18831,044,335 Ball Nov. 12, 1912 1,584,944 Johnson May 18, 1926 1,955,384Herr Apr. 1'7, 1934. 2,316,648 Giglio Apr. 13, 1943

